NEW DELHI (Thomson Reuters
Foundation) — The
World Health Organization declared India free of the crippling polio
virus on Thursday, making the country's almost two-decade-long,
multi-billion-dollar effort one of the biggest public health
achievements in recent times.

India's last case of the wild polio virus was
detected in January 2011 in a two-year-old girl in the state of West
Bengal. Three years without any new cases means a country can be
certified as polio-free.

Afghanistan, Pakistan and Nigeria are the only countries in the
world left where the virus remains endemic, largely due to violent
conflicts, weak health systems and poor sanitation.

"It is a day that all countries fought hard for, and a day when all
stakeholders come together to celebrate the victory of mankind over
a dreaded disease that, for centuries, has killed and disabled
legions."

Until the 1950s, polio crippled thousands every year in rich
countries. It attacks the nervous system and can cause irreversible
paralysis within hours of infection.

The highly contagious virus often spreads in areas with poor
sanitation and children under five are the most vulnerable.

In 1988, the Global Polio Eradication Initiative — led by
governments and supported by organizations such as WHO, Rotary
International and the U.N. Children's Fund — was launched to ensure
comprehensive, nationwide vaccination in endemic nations.

More than 350,000 children across 125 countries were being paralyzed
or killed by polio every year at that time. That figure has since
reduced by 99.9 percent and in 2013, just 406 cases of polio were
reported.

India — where more than 50,000 children were afflicted with the
virus every year — was considered one of the toughest places in the
world to eradicate polio. Many families in poor, high-risk northern
states such as Bihar and Uttar Pradesh migrate for work, while
others live in remote areas.

Millions of health workers were involved in India's mammoth drive to
immunize children by giving them polio drops.

They targeted migrant families at bus stations, on trains and at
festivals. Some used motorcycles or trekked by foot to reach
villages.

As a result, over 170 million children are now immunized every
year, with millions more targeted in house-to-house visits in a
drive which has cost the government $3 billion since 1995.

In 2009, 741 Indians fell sick with polio, nearly half the world's
cases that year. The number dropped to 42 in 2010 and only one in
2011.

In Pakistan — the only country where polio cases are increasing — gunmen frequently attack polio workers, accusing them of being
Western spies and part of a plot to sterilize Muslims. Earlier this
month, militants killed 12 members of the security escort for a
polio vaccination, detonating a roadside bomb before opening fire on
their convoy.

In neighboring Afghanistan, a three-year-old girl was found in
February to have contracted the first case of polio in the country's
capital Kabul since 2001.